1. Field of Invention
This invention relates to safety valves and, more specifically, to a safety valve having a flexible membrane that responds to sudden losses of pressure by throttling further flow from the system.
2. Description of the Prior Art
Protecting equipment from damage caused by sudden fluid pressure loss is a problem upon which a great deal of technical effort and ingenuity have been lavished. Delicate gauges, measuring instruments, and the like, are frequently exposed to relatively high fluid pressures. A sudden drop in these pressures because of a ruptured hydraulic or pneumatic line, for example, is likely to damage devices of this nature by compelling the mechanisms to respond to the pressure change at much greater than design speeds and thus to slam against the mechanism limits, or stops.
Swing-check and ball-check valves have been developed for this protective purpose. In general, these valves react to a change in the direction of hydraulic or gas flow within the system by obstructing this reverse flow. These valves are, however, subject to wear and the speed with which they respond may in itself physically shock the mechanisms that they are designed to protect.
Consequently, there is a need for a fluid safety valve that is sufficiently well dampened in its action to insure that it does not damage the very apparatus it is designed to protect. There also is a further need for a safety valve in which component wear is reduced to a minimum.